摘要
药物的无定形状态比晶态具有更大的溶解度,可以促进吸收,提高口服生物利用度,但是稳定性差,易转变为晶体状态。本文采用偏光显微镜、扫描电子显微镜、差示扫描量热法、X-射线衍射法和拉曼光谱法等研究无定形吲哚美辛的微观结晶机制,并对药物表面进行喷金包衣,厚度为10 nm,研究结晶行为变化。结果发现,无定形吲哚美辛自由表面的结晶速率远大于其内部,金包衣可显著抑制自由表面的结晶。这提示,自由表面的结晶是影响无定形药物稳定性的关键因素,纳米包衣可用于增强无定形药物的稳定性。
Amorphous drugs have higher solubility,better oral bioavailability and are easier to be absorbed than their crystalline counterparts.However,the amorphous drugs,with weak stability,are so easy to crystallize that they will lose the original advantages.Polarization microscope,scanning electron microscope,differential scanning calorimetry,X-ray diffractomer and Raman spectroscopy were used to study the microcosmic crystallization mechanisms of amorphous indometacin and the performance of the drug crystals.The results showed that the growth rate of amorphous indometacin crystals at the free surface was markedly faster than that through the bulk,and that the crystal growth rate decreased observably after spraying an ultrathin melting gold（10 nm） at the free surface of the drug.These results indicated that the high growth rates of amorphous drugs crystals at the free surface were the key to their stability and that an ultrathin coating could be applied to enhance the stability of amorphous drugs.
出处
《药学学报》
CAS
CSCD
北大核心
2011年第6期707-712,共6页
Acta Pharmaceutica Sinica
基金
国家大学生创新性实验计划(101063514)
重庆市自然科学基金项目(CSTC2009BB5106)
中央高校基本科研业务费专项资金资助(XDJK2009C076)
西南大学博士基金项目(SWUB2008032)
关键词
无定形
结晶
表面
纳米包衣
吲哚美辛
amorphou
crystallization
surface
nano-coating
indomethacin
